Honey buzzard Pernis apivorus
Honey buzzards are a Schedule 1 species and therefore care must be taken when surveying to avoid disturbance of nesting birds and/or dependant young (refer to Schedule 1 section for further details). It is therefore recommended that surveys are only undertaken by experienced raptor surveyors with the necessary fieldcraft skills to know how to avoid causing disturbance when undertaking surveys.
As described in Hardey et al. (2013), honey buzzard typically breed in locations where there is woodland cover and sufficiently large populations of social wasps, their main prey. This can include upland coniferous plantations, central hill country with mixed farmland and woodland, and lowland woodland. They typically use extensive areas of woodland, but will also use scattered woodland interspersed with farmland, heath or moorland. Their breeding range can be found on the British Trust for Ornithology Bird Atlas Mapstore.
A survey method is described in Hardey et al. (2013). However, this survey method includes a fourth visit to check for fledging success. Therefore, it may be appropriate to reduce the number of visits, or focus the visits on the earlier part of the breeding season, if the survey has an alternative aim, such as determining honey buzzard nesting presence or absence, which could potentially be determined in fewer visits and at lower risk of disturbance.
The survey method is described in detail in Hardey et al. (2013) and that reference should be read prior to undertaking honey buzzard surveys (this can be accessed here). However, a summary is provided here.
Visit Schedule
- Four visits carried out between Mid-May and August:
- Visit 1: Mid-May to mid-June. At least one visit, but more may be preferable. The survey(s) should last at least 4 hours, from 09.00 onwards and involve scanning suitable areas of woodland for displaying birds, from a suitable vantage point to check for territories (i.e. whether honey buzzards are present and occupying a territory);
- Visit 2: June. Survey to check for occupancy and to locate active nests. Once a pair on its territory has been established, observations of a honey buzzard circling up from a wood before flying off, or a bird plunging directly into a wood with folded wings are considered as good indications of breeding. Nest sites can be identified by several observers from different vantage point or by systematic searching;
- Visit 3: July. To check for active nests with young. Nests can be well hidden, with faecal droppings not being evident. However, moulted feathers, wasp combs and wasp paper can indicate the presence of a nest;
- Visit 4: August. Survey to check for fledged young (large young at least 30 days old, either still on the nest or on nearby branches).
- According to Hardey et al. (2013), due to their unobtrusive behaviour, four visits are required to confirm that a potential nesting range is unoccupied.
References
Hardey, J., Crick, H., Wernham, C., Riley, H., Etheridge, B. and Thompson, D (2013) Raptors: A Field Guide for Surveys and Monitoring (Third Edition). Scottish Natural Heritage: Edinburgh.